1. Field of the Invention
The invention relates to a device for positioning a magnetic head attached to a magnetic carrier to various tracks of a magnetic tape in a magnetic tape recording device.
2. Prior Art
A device for positioning a magnetic head to tracks of a magnetic tape in a magnetic tape recorder is described in German published patent application No. 31 12 895.5 filed Mar. 31, 1981 and corresponding to U.S. Pat. No. 4,491,890. With this known arrangement, the positioning of a magnetic head occurs upon employment of a worm drive and a screw drive connected to a drive motor, which can be a D.C. motor or a stepping motor. The worm drive is formed of a worm spindel gear secured to the output shaft of, for example, a stepping motor, and a corresponding worm wheel gear. The screw drive is formed of an inside thread of the worm wheel and a corresponding outside thread of a shaft. The magnetic head is secured to the shaft by a magnetic head carrier. The worm wheel is not displaceable in the axial direction. When the drive motor turns the worm wheel over the worm, the shaft is screwed out of or into the worm wheel, depending upon the direction of rotation. Since the magnetic head is secured to the shaft by the magnetic carrier and this carrier is correspondingly displaced in the direction of shaft movement, the magnetic head is thereby positioned to a select track of the magnetic tape in a magnetic tape recording device.
This known device is not intended for magnetic tape recorders having a particularly low overall height. Further, as a result of only a single-sided seating of the shaft, the arrangement allows for play between the various parts, however slight.